Moody was a crewman serving aboard the Federation starship USS Enterprise under Captain James T. Kirk during the mid-2260s.
In 2266, he became infected by polywater intoxication, bringing about a romantic interest in Yeoman Rand. Inspired by the lyrical ship-wide broadcasts of Kevin Riley, Moody persistently serenaded Rand with his own rendition of the song "I'll Take You Home Again, Kathleen." (TOS: "The Naked Time")
In 2268, he was present in the recreation room, when Kirk ordered a chicken sandwich and a coffee, infested with tribbles. (TOS: "The Trouble with Tribbles")